Par \Par\, n.
1. An amount which is taken as an average or mean. [Eng.]

2. (Golf) The number of strokes required for a hole or a
round played without mistake, two strokes being allowed on
each hole for putting. Par represents perfect play,
whereas bogey makes allowance on some holes for human
frailty. Thus if par for a course is 75, bogey is usually
put down, arbitrarily, as 81 or 82.

From Webster's Revised Unabridged Dictionary (1913) [web1913]:

Par \Par\, prep. [F., fr. L. per. See {Per}.]
By; with; -- used frequently in Early English in phrases
taken from the French, being sometimes written as a part of
the word which it governs; as, par amour, or paramour; par
cas, or parcase; par fay, or parfay.

From Webster's Revised Unabridged Dictionary (1913) [web1913]:

Par \Par\, n. (Zo[94]l.)
See {Parr}.

From Webster's Revised Unabridged Dictionary (1913) [web1913]:

Par \Par\, n. [L. par, adj., equal. See {Peer} an equal.]
1. Equal value; equality of nominal and actual value; the
value expressed on the face or in the words of a
certificate of value, as a bond or other commercial paper.

2. Equality of condition or circumstances.

{At par}, at the original price; neither at a discount nor at
a premium.

{Above par}, at a premium.

{Below par}, at a discount.

{On a par}, on a level; in the same condition, circumstances,
position, rank, etc.; as, their pretensions are on a par;
his ability is on a par with his ambition.